NEET PHYSICS- A BLOG FOR BETTER PRACTICE

COMMUNICATION SYSTEM Skip to main content

Ads

COMMUNICATION SYSTEM

    COMMUNICATION SYSTEM






Brief summary:

The communication system may be a system which describes the knowledge exchange between two points. the method of transmission and reception of data is named communication. the main elements of communication are the Transmitter of data , Channel or medium of communication and therefore the Receiver of data .
Types Of Communication Systems
Depending on Signal specification or technology, the communication system is assessed as follows:

(1) Analog

Analog technology communicates data as electronic signals of varying frequency or amplitude. Broadcast and telephone transmission are common samples of Analog technology.

(2) Digital

In digital technology, the info are generated and processed in two states: High (represented as 1) and Low (represented as 0). Digital technology stores and transmits data within the sort of 1s and 0s.
Depending on the channel , the communication system is categorized as follows:

1. Wired (Line communication)

Parallel wire communication
Twisted wire communication
Coaxial cable communication
Optical fibre communication
2. Wireless (Space communication)

Ground wave communication
Skywave communication
Space wave communication
Satellite communication

Examples Of Communication Systems
The following are a couple of samples of communication systems:

1. Internet

2. Public Switched Telephone network

3. Intranet and Extranet

4. Television

Elements Of Communication Systems
The definitions of the terms utilized in the communication system are discussed below.

Information

Message or information is that the entity that's to be transmitted. It are often within the sort of audio, video, temperature, picture, pressure, etc.

Signal

The single-valued function of your time that carries the knowledge . the knowledge is converted into an electrical form for transmission.

Transducer

A device or an appointment that converts one sort of energy to the opposite . An electrical transducer converts physical variables like pressure, force, temperature into corresponding electrical signal variations. Example: Microphone – converts audio signals into electrical signals. Photodetector – converts light signals into electrical signals.

Amplifier

The electronic circuit or device that increases the amplitude or the strength of the transmitted signal is named an amplifier. When the signal strength becomes but the specified value, amplification are often done anywhere in between transmitter and receiver. A DC power source will provide for the amplification.

Modulator

As the original message signal can't be transmitted over an outsized distance due to their low frequency and amplitude, they're superimposed with high frequency and amplitude wave called carrier . This phenomenon of superimposing of message signal with a carrier is named modulation. and therefore the resultant wave may be a modulated wave which is to be transmitted.

Again there are differing types of Modulation.

i. AM (AM)

The process of adjusting the amplitude of the signal wave by impressing or superimposing it on a high-frequency carrier , keeping its frequency constant is named AM .

ii. FM (FM)

Frequency modulation may be a technique during which the frequency of the message signal is varied by modulating with a carrier . it's better than deficient than AM because it eliminates noise from various sources.

iii. PM (PM)

The phase of the carrier changes the phase of the signal wave. The phase shift after modulation depends on the frequency of the carrier also . Phase modulated waves are resistant to noise to a greater extent.

Transmitter

It is the arrangement that processes the message signal into an appropriate form for transmission and subsequently reception.

Antenna

An Antenna may be a structure or a tool that's radiate and receive electromagnetic waves. So, they're utilized in both transmitters and receivers. An antenna is essentially a metallic object, often a set of wires. The electromagnetic waves are polarised consistent with the position of the antenna.

Channel

A channel refers to a physical medium like wire, cables, space through which the signal is passed from transmitter to the receiver. There are many channel impairments that affect the channel performance to a pronounced level. Noise, Attenuation and distortion to say the main impairments.

Noise

Noise is one among the channel imperfection or impairment within the received signal at the destination. There are external and internal sources that cause noise. External sources include interference, i.e. interference from nearby transmitted signals (cross talk), interference generated by natural source like lightning, solar or radiation , from automobile generated radiation, etc. The external noise are often minimised and eliminated by appropriate design of the channel, shielding of cables. Also by digital transmission external noise are often much minimised.

Internal sources include noise thanks to random motion and collision of electrons within the conductors, thermal noise thanks to diffusion and recombination of charge carriers in other electronic devices. Internal noise are often minimised by cooling and using digital technology for transmission.

⎫ a special cable design.

⎫ Proper design of the channel.

⎫ Use digital transmission

⎫ Using BPF or LPF at the receiver side.

Comments

Popular posts of the blog

ELECTRO STATICS

  ELECTRO STATICS electro statics small summary of the topic Electrostatics, as the name implies, is the study of stationary electric charges. A rod of plastic rubbed with fur or a rod of glass rubbed with silk will attract small pieces of paper and is said to be electrically charged. The charge on plastic rubbed with fur is defined as negative, and the charge on glass rubbed with silk is defined as positive. Electric charge Electrically charged objects have several important characteristics: Like charges repel one another; that is, positive repels positive and negative repels negative. Unlike charges attract each another; that is, positive attracts negative. Charge is conserved. A neutral object has no net charge. If the plastic rod and fur are initially neutral, when the rod becomes charged by the fur, a negative charge is transferred from the fur to the rod. The net negative charge on the rod is equal to the net positive charge on the fur.

Semi conductor electronics

  SEMI CONDUCTOR ELECTRONICS Brief summary: Semiconductor Basics If resistors are the most basic passive component in electrical or electronic circuits, then we have to consider the Signal Diode as being the most basic active component. However, unlike a resistor, a diode doesn't behave linearly with reference to the applied voltage because it has an exponential I-V relationship and thus can't be described simply by using Ohm’s law as we do for resistors. Diodes are basic unidirectional semiconductor devices that will only allow current to flow through them in one direction only, acting more like a one way electrical valve, (Forward Biased Condition). But, before we've a glance at how signal or power diodes work we first got to understand the semiconductors basic construction and concept. Diodes are made from a single piece of Semiconductor material which has a positive “P-region” at one end and a negative “N-region” at the other, and which has a resistivity  value some

Optics

                    OPTICS Optics is one among the branches of physics which deals with Study of light It explains about the behavior and properties of light. Optics is subdivided into two branches. Ray Optics and wave Optics Because light has dual nature. Light can be considered as a ray or it can be considered as a wave. The study of Optics also includes the construction of some Optical instruments and it Describes the behavior of visible light , Ultraviolet , And infrared light. Because light is an electromagnetic wave. Other sorts of electromagnetic wave like x-rays microwaves and radio waves exhibit similar properties. The study of optical science Is relevant to Some of the other studies including astronomy, various engineering fields, Photography And Medicine field like Ophthalmology and optometry. Also Optics include some practical applications We found in variety of Technologies In our daily to day life Including mirrors, lenses, telescopes microscopes, lasers and fiber